I don't hate Kung Jin, but I'm not a fan of his design or gameplay. His design is very boring, as well as his colour scheme - alot of muddy and bland colours, nothing about him stands out as cool or interesting.
As for his gameplay, he's got WAY too much going on for him. Both a bo staff that can spit fire, which is also a bow that can shoot arrows, and he has a chakram that he can throw... why all those projectiles? It's like NRS just threw in whatever random idea they could and gave them to Kung Jin. He's like a mix of Jade, Nightwing, Green Arrow with a sprinkle of Tanya (the flip kick) and Liu Kang (the flying kick) thrown in there, it's just ALOT of random stuff for one character. There's no focus in his gameplay.
Personality wise... he's a bit of a whiny b#tch. And his whole superiour complex, thinking he's better than everyone, and having issues with authorities... he truly is the embodiment of an angry teenager who sits at home listening to emo punk, thinking the world sucks. Hopefully he'll grow out of that in MK11.
He truly doesn't have any redeeming qualities. Even Mileena and Tanya do the gay thing alot better, so I can't even give him that.